Using 14 sets of GPS sounding data of a cold air process,the height of atmospheric boundary layer before and after the cold air transit is determined by the potential temperature gradient method,and the impact of cold air process on the structure of atmospheric boundary layer is also analyzed.Results show that the cold front transit increases the static instability of marine atmospheric boundary layer,enhances the convective activity in the boundary layer,and the greater the static instability of the boundary layer in the area closer to the front after front transit.The cold front transit makes the mean height of the boundary layer increase,and the gradient of temperature inversion at the top of the boundary layer increase.Combined with the ERA-Interim reanalysis data,it is concluded that there is a significant positive correlation between the height of atmospheric boundary layer and the static stability (sea-air temperature difference),and the correlation coefficient is 0.73.The higher the sea-air temperature difference,the higher the height of atmospheric boundary layer.